Dissertations / Theses on the topic 'Superstructure'
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Abernathy, Frank Wesley. "Studies on eukaryotic DNA superstructure." The Ohio State University, 1988. http://rave.ohiolink.edu/etdc/view?acc_num=osu1299775340.
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Furner, James. "Marx's Conception of Basis and Superstructure." Thesis, University of Sussex, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.486981.
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This study begins with a critique of G. A. Cohen's power-oriented account of the economic 'basis' and his claim that the 'superstructure' is functionally explained. Thereafter, Marx's writings are interrogated in chronological order, focusing on The German Ideology, The Eighteenth Brumaire of Louis Bonaparte and the Capital volumes and drafts. An alternative interpretation of the basis and superstructure metaphor is proposed in light of a three-way distinction, first outlined in The German Ideology, between material production, customary consciousness and non-economic labour. Material production, the system of interactional production relations, sustains a kind of linguistic reflection by economic agents on their practice which imposes limits on non-economic labour. The 'idealistic superstructure', a term which Marx adopts in response to Stirner's account of 'hierarchy', consists of the formulation and implementation of 'universal' notions. It arises once material production is 'autonomised', only disappearing entirely in 'developed' communism. One may distinguish between the technical autonomisatlon of material production, individuals' perpetuated engagement in a division of labour, and their formal autonomisation, the confinement to an economic class. Technical autonomisation establishes a 'contradiction' between particular and common·interests, which results in conflict, at the same time as it sustains customary beliefs in 'universal' notions whose organised assertion may hold this conflict in check. In the case of modern society, the only specific case Marx outlines, the generalisation of commodity exchange is the root of customary notions of abstract equality and individualistic freedom which provide the resources for the construction of a 'Rechtsstaat'. The French state under Bonaparte is a kind of worst-case scenario of the modem 'Rechtsstaat'
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Hou, Qianqian. "Life Cycle Assessment of Cruising Ship Superstructure." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-160456.
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This thesis project was conducted to compare the environmental impacts between two types of material for a superstructure of cruising ship (Norwegian Gem) using life cycle assessment (LCA) methods. With the increasing price of industrial raw materials and finite resources, more and more corporations or manufacturers endeavor in seeking more economical materials and less environmental impacts within the ship building field. In recent years, lightweight composite material has been applied in various industrial fields, for instance, green buildings, aircraft and wind turbine blade. In order to study impacts of steel superstructure and composite material superstructure of the ship, a detail study was conducted which using the comparative LCA method and SimaPro software. Two different superstructures are compared, steel superstructure and sandwich material superstructure. The results showed thatover the life cycle the environmental impacts of sandwich superstructure type are much less than for the steel superstructure. The main contribution of impacts over the life time is operation phase due to fuel consumption. When increasing the waste recycling section for composite structure, the influence on environment has an obvious decrease compared to steel superstructure.
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Dahdah, Tawfiq. "Superstructure optimization of hybrid thermal desalination configurations." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/85452.
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Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2013.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 95-105).
As the global demand for freshwater continues to increase, a larger number of resources are dedicated to seawater desalination technologies. In areas with high temperature and salinity water, thermal desalination technologies are often employed. In other areas, reverse osmosis technologies are more popular. While both these technologies have witnessed improvements in recent years, economic and performance issues still pose significant barriers to their universal implementation, which has left many countries, including ones bordering oceans and seas, suffering from dire water scarcity issues. This thesis proposes a methodology which enables the identification of improved thermal-based desalination structures. It is based on the notion of superstructure, which allows for the representation of numerous feed, brine and vapor routing schemes. A superstructure is developed. By adjusting the flow routings, the superstructure is capable of representing the common thermal desalination structures, as well as an extremely large number of alternate structures, some of which might exhibit advantageous behavior. The superstructure is built around a repeating unit which is a generalization of an effect in a multi-effect distillation system (MED) and a stage in a multi-stage flash system (MSF). Allowing for just 12 repeating units, more than 1040 different structures can be represented. The superstructure is thus proposed as an ideal tool for the structural optimization of thermal desalination systems, whereby the optimal selection of components making up the final system, the optimal routing of the vapors as well as the optimal operating conditions are all variables simultaneously determined during the optimization problem. The proposed methodology is applicable to both stand-alone desalination plants and dual purpose (water and power) plants wherein the heat source to the desalination plant is fixed. It can be extended to also consider hybrid thermal-mechanical desalination structures, as well as dual purpose plants where the interface of power cycle and desalination is also optimized for. A multi-objective structural optimization of stand-alone thermal desalination structures is performed in Chapter 2, whereby the performance ratio of the structures is maximized while the specific area requirements are minimized. It is found that for any particular distillate production requirement, alternate structures with non-conventional flow patterns require lower heat transfer areas compared to commonly implemented configurations. Examples of these non-conventional configurations are identified, which include a forward feed - forward feed MED structure, involving the integration of two forward feed MED plants. Chapter 3 highlights how the superstructure can be adapted to optimize integrated thermal desalination and thermal compression systems. Specifically, the conducted study investigates whether there is any merit to the thermal compression of vapor streams produced in intermediate MED effects as opposed to the common practice of compressing vapors produced in the last effect. The study concludes that intermediate vapor compression results in significant reductions in area requirements, as well as significant increases in maximum distillate production capacities. Moreover, the study confirms that the optimal location of vapor extraction is heavily dependent on the exact distillate production requirement in question. Two novel configuration forms are informed by the optimization. The first is an integrated MED-TVC + MED + MSF system, while the second is an integrated MED-TVC + MSF system.
by Tawfiq Dahdah.
S.M.
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ANKIT, KUMAR. "SKEW BEHAVIOR IN DESIGN OF STEEL COMPOSITE SUPERSTRUCTURE." Thesis, DELHI TECHNOLOGICAL UNIVERSITY, 2021. http://dspace.dtu.ac.in:8080/jspui/handle/repository/18839.
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The skew effect in a bridge makes the designing and analyzing of bridge more complex.
Bridge design is more troublesome by considering skew angle in the engineering
community, so there is a requirement to study the effect of skew angle on the skewed
bridges such as bending moment, shear force, and other parameters. This investigation based
on the effect of skew angle on the design of steel composite super structures in bridges.
Four models have been created and have been utilized by using Finite element-based
software STAAD PRO V8i. Skew angles are taken as 0, 15, 30, and 45 degrees and all
models are exposed to IRC class A, IRC class 70R vehicle and Special Vehicle loading.
Results for skewed bridges are in examination with the straight or non-skewed bridges.
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Umair, Shakila. "Environmental Impacts of Fiber Composite Materials : Study on Life Cycle Assessment of Materials used forShip Superstructure." Thesis, KTH, Miljöstrategisk analys, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-46483.
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This thesis was conducted to investigate the impacts of fiber composites on theenvironment. Composition, properties and application of fiber compositeswere also studied. On the basis of its application, taking into account previousstudies information was gathered related to impacts of these fiber composites.In order to study impacts of fiber composites in marine application a detailstudy was conducted where using the LCA method and Sima Pro softwarethree ship superstructures of the ship Stena Hollandica were compared. Thesewere steel superstructure, balsawood core superstructure and PVC foamsuperstructure. The results showed that over the lifecycle the impacts of PVCand balsawood superstructure were almost the same and were better than thesteel superstructure. The main contribution of impacts over the lifetime wasdue to the fuel consumed. When only the superstructure was consideredseparately from the life cycle the best choice was balsawood and the PVC foamsuperstructure had the most impacts. Overall it was found that balsawoodcould be considered as the best alternative as a material for the construction ofthis ship superstructure.
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McBride, Kevyn C. "Thermal stresses in the superstructure of integral abutment bridges." Morgantown, W. Va. : [West Virginia University Libraries], 2005. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=4331.
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Thesis (M.S.)--West Virginia University, 2005.Title from document title page. Document formatted into pages; contains x, 131 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 115-122).
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Kato, Ryoji. "Modelling of Ship Superstructure Icing : Application to Ice Bridge Simulators." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for marin teknikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-18655.
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Increasing activities on high north regions bring about a demand of safety ship navigation. Under severe weather condition considerable amounts of ice may accumulate on marine structures. Ice bridge simulator is of importance in terms of training for qualified maritime personal. The new ice module to fit for additional problem for the ship icing is introduced with low reality into bridge simulator. Regarding this our aim is to develop ice model that calculate ice load on the ship structure and stability change include parameters of air temperature, relative wind speed, wave height etc. As a result of literature survey theoretical and empirical method with its algorithm is studied. The ice thickness on cylinder and plate as a representative element of the structures are calculated as a function of liquid water content, relative wind speed and freezing fraction for simplified ship superstructures to include the effect of trapped water on deck. Since we have to deal with several thousand of element to be calculated every seconds including iteration process, computer should be used, hence new ice model is proposed by using computer language C++. In case study 300 tonnage size coast guard vessel is selected as a model ship. Under assumptions that those external parameters are stable in the duration of simulation, proposed model is validated. As a result proposed model could simulate total ice load and following stability change, with error of rolling period after 20 hours simulation being 0.14 sec compared to full scale measurement.
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Monzon, Eric V. "Seismic response of isolated bridge superstructure to incoherent ground motions." abstract and full text PDF (free order & download UNR users only), 2006. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1438943.
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Cox, S. "Observation and control of the low temperature superstructure in manganites." Thesis, University of Cambridge, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.598107.
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The work in this dissertation is focused on the insulating side of the La1-xCaxMnO3 and Pr1-xCaxMnO3 phase diagram, in particular on the low temperature ‘charge ordered’ phase. This phase exhibits a superstructure whose periodicity depends on the doping of the sample, among other factors. Firstly the microscopic nature of the charge ordered phase is probed using a variety of techniques including TEM, heat capacity measurements and neutron diffraction measurements. Secondly, the charge ordered phase is controlled via the manipulation of strain. In the first set of experiments, polycrystalline samples are subject to extrinsic effects, and so although it is possible to observe spatial variations in the superstructure, it is not possible to systematically control possible causes of the variation. By growing thin films it was possible to control the level of strain in the film, which is one of the extrinsic effects. This creates a spatial variation in the superstructure which could be observed. The results of this experiment can then be used to provide insight into the small scale nature of the charge ordering superstructure.
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Wilson, Daniel W. "Soil-pile-superstructure interaction in liquefying sand and soft clay /." Davis, Calif. : Center for Geotechnical Modeling, Dept. of Civil and Environmental Engineering, University of California, Davis, 1998. http://cgm.engr.ucdavis.edu/download/html.
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Youssef, Mohamed Ahmed Mohamed. "Intelligent selection of concrete bridge superstructure construction methods in Egypt." Thesis, Loughborough University, 2006. https://dspace.lboro.ac.uk/2134/35073.
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The selection process of bridge superstructure construction methods in Egypt currently depends on experts' knowledge, experience and intuition and is not supported by systematic procedures. This means that the decisions made can be sub-optimal, not taking account of all the necessary considerations. Invariably, these are cost, schedule and quality problems. This thesis is concerned with the development of a decision support system that provides a systematic and structured framework to improve the current selection process of bridge superstructure construction methods.
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Belletante, Ségolène. "Méthode multi-échelle pour la conception optimale d'une bioraffinerie multi-produit." Thesis, Toulouse, INPT, 2016. http://www.theses.fr/2016INPT0072/document.
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De nos jours, de nouvelles technologies sont développées pour produire efficacement des produits dérivés de matières premières autresque le pétrole, comme par exemple la biomasse. En effet, la biomasse et plus spécifiquement la biomasse non alimentaire possède un fort potentielcomme substitut aux ressources fossiles pour des raisons environnementales, économiques et politiques. Dans ce contexte, l’étude des bioraffineries offre de nouvelles opportunités pour le Process System Engineering et plus particulièrement pour des activités de recherche quivisent la conception de systèmes constitués d’entités interconnectés. En effet, le verrou principal se concentre sur la modélisation et l’optimisation multi-échelle de la bioraffinerie qui permet l’intégration de plusieurs échelles spatiales allant de l’échelle moléculaire à celle de l’unité de production. Ces différentes échelles sont essentielles pour décrire correctement le système puisqu’elles interagissent en permanence. La forte dilution des courants est le meilleur exemple pour illustrer ces interactions. En effet, la présence d’eau induit de nombreux problèmes thermodynamiques (azéotropes, etc.) à l’échelle moléculaire, ce qui impacte fortement la topologie du procédé notamment sur les étapes de séparation, de purification et detraitement des purges (pour limiter les pertes en produits). Ainsi, la performance de la séquence d’opérations unitaires de l’étape de purification dépend entièrement de la concentration en eau. De plus dans la conception de bioraffinerie, il est fréquent de coupler fermentation et séparation afin d’améliorer les performances de la fermentation et de limiter la présence d’eau dans l’étapede purification. Par ailleurs, la grande quantité d’eau à chauffer ou refroidir entraine la nécessité de réaliser l’intégration énergétique du réseaud’échangeurs du procédé afin de minimiser le coût les dépenses énergétiques. L’objectif de ce travail est alors de proposer une méthodologie générique et les outils associés afin de lever certains verrous de la modélisation et l’optimisation multi-échelle de la bioraffinerie. Basée sur une approche par superstructure, la finalité de la méthodologie est d’évaluer les performances des alternatives étudiées en termes technico-économiques, environnementaux et d’efficacité énergétique en vue de son optimisation multi-objectifs pour trouver la voie de traitement optimale pour le(s) bioproduit(s) d’intérêt. Le cas d’application retenu se focalise sur la production de biobutanol à partir du système Acétone-Butanol-Ethanolet d’une biomasse d’origine forestière. La première étape de la méthodologie proposée concerne la création de la superstructure de la bioraffineriebasée sur une décomposition de cette dernière en 5 étapes principales : le prétraitement, la fermentation, la séparation, la purification et letraitement des purges. Ensuite, la seconde étape consiste à modéliser chaque alternative de procédé. Cette modélisation utilise un modèlethermodynamique à coefficients d’activité afin de décrire le comportement fortement non-idéal des molécules du milieu. De plus, l’intégration du traitement des purges et de l’intégration énergétique durant cette étape permet d’améliorer le procédé. Enfin, la dernière étape s’intéresse à l’optimisation multiobjectif qui se focalise sur différents aspects : maximisation de la production, minimisation des coûts, du prix minimal de vente des bioproduits, des pertes en produits et de l’impact environnemental. Cette dernière étape inclut également des études de sensibilité sur les différents paramètres de la méthodologie : opératoires, économiques, environnementaux... A l’issu de l’optimisation, un compromis seratrouvé afin d’obtenir une bioraffinerie durableNowadays, to replace chemical products derived from petrol, new technologies are developed to produce products derived from others feedstock than crude oil like biomass. Indeed, biomass and especially nonfood biomass has a high potential as substitute due to its environmental, economic and political interests. Inthis context, the study of biorefineries offers new opportunities in the Process System Engineering and especially in research activities which aim to design systems with interlinked compounds. Indeed, the main hurdle focuses on the modeling and the multiscale optimization of thebiorefinery that allows integratingseveral spatial scales from the molecular scale to the plant scale. These scales are essential to describe accurately the system because they interact. The large dilution of flows is the best example to show these interactions. Indeed, water induces many thermodynamic problems (azeotropes, etc.) at the moleculescale, that impact on the process design and mainly on the separation, the purification and the treatment of purges (to limit losses of products). In consequence, the sequence of unit operations of the purification step depends of the water concentration. Furthermore, in the design of the biorefinery, the fermentation and theseparation are usually combined in order to improve performances of the fermentation and limit the water concentration in the purification step. Moreover, the large amount of water that needs to be heated or cooled induces the need of the energy integration of the heat exchangers network to minimize energy consumption. The aim of this work is to propose a generic methodology with connected tools in order to overcome some hurdles caused by the modeling and the multiscaleoptimization of the biorefinery. Based on the superstructure approach, the purpose of the methodology is to estimate performances of considered alternatives in the technical, economic, environmental and energy efficient aspects in preparation for the multiobjective optimization which finds the optimal process for the productionof the interesting bioproduct. This work focuses especially on the production of biobutanol through the Acetone-Butanol-Ethanol system from forest biomass. The methodology begins with the creation of the superstructure of the biorefinery composed by 5 major steps: the pretreatment, the fermentation, the separation, the purification and the treatment of purges. Next, the methodology consists in modeling each alternative of process. It integrates a thermodynamic model with activity coefficients in order to describe accurately the greatly nonideal behavior of molecules. Moreover, the treatment of purges and the energy integration are integratedat this step in order to improve the process. Finally, the last step interests to the multiobjective optimization which focuses on different aspects: the maximization of production and the minimization of the costs, the minimal selling price of bioproducts, the losses of bioproducts and the environmental impact. This step includes also sensitivity analysis on different parameters of the methodology: operating, economic, environmental… After the optimization, a compromise is made in order to obtain sustainable biorefinery
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Isafiade, Adeniyi Jide. "Interval based MINLP superstructure synthesis of heat and mass exchange networks." Doctoral thesis, University of Cape Town, 2007. http://hdl.handle.net/11427/5315.
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Includes abstract.Includes bibliographical references (leaves 153-157).
Name inverted on t.p.
This study presents a new technique for synthesizing heat and mass exchange networks. The method involves generating superstructures using the temperature/composition interval concept from the physical insight approach. The superstructures are partitioned into temperature/composition intervals using the supply and target temperatures/compositions of either the hot/rich or cold/lean set of streams. The opposite kind of streams are made to participate (float) in all the intervals defined. Their ability to exchange heat/mass in these intervals is however subject to thermodynamic feasibility. The resulting superstructure is optimised as a mixed integer non linear programming (MINLP) model. The superstructure is hot/rich streams based if hot/rich streams are used to define the intervals otherwise it is cold/lean stream based.
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Kaaria, Christopher. "Investigating the impact of ship superstructure aerodynamics on maritime helicopter operations." Thesis, University of Liverpool, 2012. http://livrepository.liverpool.ac.uk/11737/.
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The work reported in this thesis has investigated the impact of ship superstructure geometry on helicopter operations to the flight decks of naval warships. Ship-Helicopter operating limits for military frigates and destroyers are often restricted in difficult weather conditions because of excessive pilot workload caused by the unsteady ship airwake. Experiments have been conducted in a water tunnel using a specially designed Airwake Dynamometer (AirDyn) to characterise the steady and unsteady aerodynamic loading of a helicopter immersed in the airwake of a generic ship that has been called the Shortened Research Frigate (SRF). The AirDyn is a 1:54 model-scale helicopter, mounted on a six-component force block; it has a simplified spinning main rotor and fuselage based on a Merlin AW-101. The AirDyn has been shown to be an effective tool for characterising the steady and unsteady aerodynamic loading of a helicopter model in a ship’s airwake and the aerodynamic loads measured by the AirDyn were found to correlate with at-sea and simulation flying experience for a range of Wind-Over-Deck (WOD) conditions and ship geometry configurations. The airwakes of the SRF without the presence of a helicopter model have also been investigated using unsteady Computational Fluid Dynamics (CFD). A Detached-Eddy Simulation (DES) approach was used for the turbulence modelling as it has been shown to be capable of capturing the bluff-body type flow features typical of ship airwakes. Analysis of the CFD data revealed the underlying aerodynamic causes of the observed loading characteristics of the AirDyn. A range of ship geometry modifications were made to the SRF to determine the feasibility of mitigating the adverse effects of the airwake by modifying existing ships or by improving the designs of future ships. A range of modifications to the windward hangar side-face of the SRF were tested using the AirDyn and were found to reduce the severity of unsteady loads by up to 55% for oblique WOD angles (Green 30°-45°) at important locations through the flight path of a standard Royal Navy deck-landing manoeuvre. Unsteady CFD analysis showed that the modifications controlled the flow separation from the top edge of the windward hangar side-face in such a way as to reduce the height and the angle of the separated flow and thus the severity of the unsteady flow structures being drawn into the main rotor of the AirDyn. The unsteady CFD data computed for the baseline and modified SRF ship geometries was also integrated into the University of Liverpool’s motion-base flight simulator and piloted flight simulation trials were conducted to determine the impact of the ship modifications on pilot workload. The results of the simulation flight trials confirmed the usefulness of the AirDyn as a tool for predicting pilot experience and showed that it is feasible to modify ship superstructures to the extent that tangible reductions in pilot workload are achieved.
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Price, Thomas. "Influence of embankment/superstructure interaction on the seismic response of bridges /." Thesis, Connect to this title online; UW restricted, 1997. http://hdl.handle.net/1773/10199.
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Bouvry, Benjamin. "Développement de matériaux réfractaires à haute émissivité pour superstructure de fours verriers." Thesis, Orléans, 2015. http://www.theses.fr/2015ORLE2002.
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Afin de répondre aux nouvelles exigences liées au développement durable, des entreprises telles que Saint- Gobain sont amenées à développer de nouveaux produits en vue de réduire les coûts de fonctionnement de leurs systèmes de fabrication de verre ainsi que les rejets de gaz à effet de serre. Une façon d’atteindre ces objectifs est d’améliorer l’isolation thermique des fours verriers par un accroissement des propriétés émissives des matériaux réfractaires constituants ces fours tels que le Jargal M et la BP mullite. La piste choisie pour l’amélioration des performances radiatives est la fonctionnalisation des matériaux de base afin qu’ils atteignent des hauts niveaux d’émissivité à la température de fonctionnement des systèmes de production. Cette stratégie permet de conserver les propriétés de résistance pyroscopique des matériaux de base tout en améliorant leurs performances radiatives. Une optimisation de ces deux matériaux a été effectuée par dopage avec des oxydes d’éléments de transition connus pour induire des propriétés hautement émissives dans le domaine de transparence de milieux diélectriques. Diverses techniques d’élaboration ont été testées comme le dopage en masse ou par imprégnation, afin de proposer des solutions efficaces et viables industriellement. L’étude de ces matériaux dopés a été réalisée par spectroscopie d’émission infrarouge en température à l’aide d’un dispositif expérimental développé au laboratoire CEMHTI utilisant un chauffage par laser CO2. Des observations par microsonde et microscopie électronique à balayage ont permis de corréler l’amélioration des propriétés radiatives à la texture, phases en présence et répartition des éléments dopants au sein des matériaux. Une étape de modélisation a également permis de compléter la démarche expérimentale en mettant en évidence l’influence de la texture et de la composition sur les propriétés radiatives. Cette partie intègre diverses étapes allant du traitement d’images issues de μ-tomographie X, la production de matériaux numériques ayant des textures maitrisées et leur caractérisation par simulation numérique utilisant les lois de l’optique géométrique et la méthode de lancer de rayonsEvolution of global economy and green policy leads companies, like Saint-Gobain, to develop new productsto reduce the cost of their glass making systems and greenhouse gas emissions from glass furnaces. It isnecessary to improve thermal insulation of furnaces by increasing emittance property of refractory materialslike Jargal M and BP mullite. A way to improve radiative properties is the functionalization of materials toreach high levels of emissivity at working temperature and to keep refracterity of base materials.Improvement of optical properties of materials was made by adding emissive elements like transition oxides,known to induce high emissivity property in the transparent region of dielectric material. Several dopingtechnics were tested, for example mass doping or elements diffusion, to propose efficient and usefulsolutions for industries. Optical characterization was performed with an infrared spectrometry devicedeveloped in the CEMHTI laboratory, allowing measurement at high temperature thanks to CO2 laserheating. Microsonde and scanning electron microscopy observations were also done to correlateimprovement of radiative behavior with texture, phases and localization of doping elements into materials. Asimulation step has also been developed to complete experimental measurements and to show texture andvolume influences on radiative properties. This numerical procedure mixed image treatment from μ-tomography X analysis, generation of numerical samples with controlled texture and their characterization bynumerical simulation using geometrical optic laws and rays tracing procedure
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Hamiche, Ali. "Structure du nucleosome et ses implications pour la superstructure de la chromatine." Paris 6, 1995. http://www.theses.fr/1995PA066796.
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Cette these a ete consacree a l'etude de la structure du nucleosome et plus particulierement au probleme du nombre de tours d'adn enroule autour du nucleosome. Ce nombre de tours est admis generalement etre egal a deux, bien qu'il s'agisse la d'une supposition basee sur la structure cristallographique du cur du nucleosome. Nous avons aborde ce probleme d'une maniere originale, en reconstituant un nucleosome unique sur un minicercle d'adn et sur un petit fragment lineaire. La mesure du deroulement thermique de l'adn associe aux histones dans le meme nucleosome circulaire montre que seulement 109 pb sont en interaction avec celles-ci, ce qui correspond a 1,3 tour d'adn enroule autour du nucleosome. Dans ce cas, les adn entrant et sortant du nucleosome ne sont pas croises. L'addition de h5 a ces mononucleosomes est accompagnee d'une augmentation importante de la reduction du nombre d'enlacements (|lk|), qui passe de 1 a 1,75 ainsi que d'une forte acceleration des mobilites electrophoretiques sur gel. Ceci confirme qu'avant addition de h5 le nucleosome contenait moins de 2 tours d'adn. Nous avons egalement montre que la queue c-terminale de h5 interagit en meme temps avec les 2 adn entrant et sortant du nucleosome pour former une structure a 4 brins, inconnue jusqu'alors. D'autre part l'observation des mononucleosomes, cette fois lineaires, par microscopie cryo-electronique confirme l'absence de croisement. L'ensemble de ces resultats definit non seulement la topologie reelle de l'adn sur le nucleosome, mais, en montrant la fonction exacte de la queue c-terminale de h5, impose des contraintes precises pour la formation de la superstructure chromatinienne
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Azeez, Oluwatosin Sarafa. "Supply and target-based superstructure synthesis of heat and mass exchange networks." Doctoral thesis, University of Cape Town, 2011. http://hdl.handle.net/11427/5342.
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Includes abstract.Includes bibliographical references.
This study presents three new methods for superstructure synthesis of heat exchanger networks (HENs) and mass exchanger networks (MENs) that involve the use of key parameters in HEN and MEN to define superstructure intervals. The key parameters are the stream supply and target temperatures/compositions. The Supply-Based Superstructure (SBS) uses the supply temperatures/compositions of both the hot/rich streams and the cold lean streams. The Supply and Target-Based Superstructure (S&TBS) uses the supply temperatures/compositions of hot/rich streams and the target temperatures/compositions of cold/lean streams for the definition of the superstructure intervals. The Target and Supply-Based Superstructure (T&SBS) uses the target temperatures/compositions of hot/rich streams and the supply temperatures/compositions of cold/lean streams for the definition of the superstructure interval boundaries.
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Patty, Jill Kathleen. "Longitudinal seismic response of concrete substructure-to-steel superstructure integral bridge connections /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC IP addresses, 2002. http://wwwlib.umi.com/cr/ucsd/fullcit?p3061626.
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Dehghanpoor, Sichani Ahmad. "Soil-pile-superstructure systems under combined horizontal and vertical strong ground motions." Thesis, Queensland University of Technology, 2021. https://eprints.qut.edu.au/207885/1/Ahmad_Dehghanpoor%20Sichani_Thesis.pdf.
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Highway bridges considered as important but possibly vulnerable superstructures must be studied under natural hazards, such as earthquakes, tsunamis, hurricanes. This thesis was a novel investigation on reinforced concrete bridges under coupled horizontal and vertical ground motions. A variety of ground motions has been examined for different classification of bridges and novel conclusions have been presented in the probabilistic and deterministic frameworks.
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Nawaz, Muneeb. "Synthesis and design of demethaniser flowsheets for low temperature separation processes." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/synthesis-and-design-of-demethaniser-flowsheets-for-low-temperature-separation-processes(101e8d29-7e02-4b3f-b3a7-be2a36acc1f7).html.
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A demethaniser process is characterised by interactions between the complex distillation column and other flowsheet units, including the turbo-expander, flash units, multistream exchangers and refrigeration system. When a design problem dealing with demethaniser flowsheets is approached in a systematic way, the number of alternatives to be studied is generally very large. The assessment of all possible flowsheets with numerous options is a time consuming task with many simulations required to select the most economic option. This research presents a systematic approach for demethaniser flowsheet synthesis to generate cost-effective designs with minimal time and effort. A demethaniser column has many degrees of freedom, including the operating pressure, multiple feeds, the number and duty of side reboilers and the flow rate of the external reflux stream. The additional feed and side reboiler streams enhance the efficiency of the process, but complicate process modelling. The number of design variables is also augmented by additional degrees of freedom such as the location and the order of feeds, the number of stages and the reflux ratio in the column. The complexity of the demethaniser column precludes the use of the Fenske–Underwood–Gilliland shortcut design method. A semi-rigorous boundary value method is proposed for the design of complex demethaniser columns for application within an optimisation framework for process synthesis and evaluation. The results of the proposed design methodology are shown to be in good agreement with those of rigorous simulation. A simplified flowsheet simulation model based on a sequential modular approach is developed that is able to account for various configurations and inter-connections in the demethaniser process. Improved shortcut models for flash units, the turbo-expander, compressor and refrigeration cycle have been proposed for exploitation in a synthesis framework. A methodology accounting for heat integration in multistream exchangers is proposed. The simplified simulation model is applied for the optimisation of a flowsheet of fixed configuration. The nonlinear programming technique of sequential quadratic programming (SQP) is used as the optimisation method. A case study is presented to illustrate the application of the optimisation approach for maximising the annual profit. A generalised superstructure has been proposed for demethaniser flowsheet synthesis that includes various structural combinations in addition to the operational parameters. The various options included in the superstructure and their effects on flowsheet performance are discussed. A stochastic optimisation technique, simulated annealing, is applied to optimise the superstructure and generate energy-efficient and cost-effective flowsheets. The application of the developed synthesis methodology is illustrated by a case study of relevance to natural gas processing. The results allow insights to be obtained into the important trade-offs and interactions and indicate that the synthesis methodology can be employed as a tool for quantitative evaluation of preliminary designs as well as to facilitate evaluation, selection and optimisation of licensed demethaniser flowsheets.
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Mackney, Michael D. A. "Hull-superstructure interaction : generic models, preprocessors, numerical and experimental models, and parametric studies." Thesis, University of Portsmouth, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.333868.
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Sellami, Mohamed. "Optimisation et aide au choix de solutions globales fondations-superstructure en construction métallique." Chambéry, 1995. http://www.theses.fr/1995CHAMS001.
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Nous proposons dans cette these le systeme informatique focome pour la conception des postes fondations et superstructure en cm ainsi qu'une methodologie pour l'acquisition de nouvelles connaissances concernant l'optimisation de solutions globales fondations-superstructure. Le systeme focome s'appuie sur une modelisation conceptuelle des informations concernant les trois domaines techniques: le sol, les fondations et la superstructure. La base de donnees commune, et les modules d'evaluations techniques de la structure et des fondations sont implementes avec le langage oriente objet c++. Nous avons dote le systeme d'une methode d'optimisation du cout global des materiaux de la construction (poids d'acier et volume de beton). Cette methode consiste a generer automatiquement toutes les configurations realisables d'une structure en faisant varier certaines variables de conception: types d'appuis, types de nuds, etc et a etablir un diagnostic pour le dimensionnement optimal de ces configurations. Pour acquerir de nouvelles connaissances concernant la recherche de solutions optimales globales fondations-superstructure, le systeme focome peut etre utilise sous forme d'un simulateur: des simulations portant sur les portiques a nefs multiples ont ete effectuees en faisant varier les parametres caracterisant le sol et la superstructure les resultats obtenus ont ete exploites selon une methode adaptee permettant la deduction de regles expertes. Cette methode est basee sur les principes d'analyse multicritere. Les criteres retenus pour cette etude sont la quantite de beton des massifs de fondations et la quantite d'acier de la superstructure metallique
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Wu, Haiyong. "Influence of live-load deflections on superstructure performance of slab on steel stringer bridges." Morgantown, W. Va. : [West Virginia University Libraries], 2003. http://etd.wvu.edu/templates/showETD.cfm?recnum=3117.
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Thesis (Ph. D.)--West Virginia University, 2003.Title from document title page. Document formatted into pages; contains xx, 332 p. : ill. (some col.), map. Includes abstract. Includes bibliographical references (p. 256-264).
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Grabovac, Ivan, and ivan grabovac@dsto defence gov au. "Composite Reinforcement for Naval Ships: Concept Design, Analysis and Demonstration." RMIT University. Applied Sciences, 2006. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20070209.151724.
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This thesis outlines the development of composite reinforcement technology for a ship's aluminium alloy superstructure. The work objective aimed to alleviate stress concentration in parts of the superstructure prone to fatigue-induced cracking. This is a novel approach to ship repair, which promises reduction in the cost of maintenance primarily due to greater efficiency and lower cost of repair. The work was conducted over approximately 12 years. It commenced in the late 80s with laboratory research and development and concluded in 2000 after completion of a seven-year trial on board a navy ship. Two carbon fibre composites, (5 m x 1 m consisting of a 25-ply laminate), were adhesively bonded to the 02-deck on the port and starboard sides. It was found that upgrading the structure using composites was effective, making it able to withstand service fatigue stresses. Finite element modelling and strain measurements on board the ship showed that critical stress concentration could be alleviated through stress redistribution. For the duration of the trial, no cracking of aluminium alloy deck in the vicinity of the reinforcements was reported. Both composite reinforcements exhibited good performance and remained in service after the end of the trial. However, the marine environment did cause some non-structural, edge debonding of the glass fibre reinforced overlay at the composite-metal interface. This overlay was designed to provide surface protection to the underlaying carbon reinforcement. Bond degradation was patchy. It occurred after about three years in service, most probably due to a combination of thermal cycling (solar heating/cooling) and water ingress at the interface. A new edge sealing method restored its durability and it required no further attention. This experiment was successfully demonstrated on board an active navy ship. The work proved that an effective and durable repair of a ship structure using non-metallic repair technology is feasible. Composite reinforcements prevented deck cracking and removed any need for welded repairs, thereby reducing the cost of ship maintenance. For further cost reduction it is recommended to adopt the principle of reverse engineering to simplify the technology for dockyard use.
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Ali, Sk Imran [Verfasser], and Sander van [Akademischer Betreuer] Smaalen. "Synthesis, Superstructure, Vacancy-Ordering of Intercalated Transition Metal Dichalcogenides / Sk Imran Ali. Betreuer: Sander van Smaalen." Bayreuth : Universität Bayreuth, 2014. http://d-nb.info/1061071936/34.
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McLaren, Victoria Leah. "A study of rock salt superstructure oxide phases and their possible applications in lithium ion batteries." Thesis, University of Sheffield, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.398376.
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Teh, Peh Chiong. "Applications of superstructure fibre Bragg gratings for optical code division multiple access and packet switched networks." Thesis, University of Southampton, 2003. https://eprints.soton.ac.uk/46105/.
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This thesis describes the research on the implementation of all-optical code generation and recognition based on superstructure fibre Bragg grating (SSFBG) for use in Optical Code Division Multiple Access (OCDMA) systems and also in high-speed all-optical packet switched networks.These results highlight the precision and flexibility of the continuous grating writing process and show that the SSFBG technology represents a promising technology not just for OCDMA but an extended range of other pulse shaping, and associated optical processing applications such as required within optical packet switched networks
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WU, CHANG. "Exploring the Boundary of Perturbative Quantum Chromodynamics - Resummation of Non-Global Logarithms and Soft Superstructure of Jets." Doctoral thesis, Università degli studi di Genova, 2021. http://hdl.handle.net/11567/1045608.
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This thesis arises in the context of the precision era of Higgs physics from the recent high accuracy data at the Large Hadron Collider (LHC). With the data of an unprecedented level of precision, the theoretical error is now lagging behind. In addition, the accurate theoretical prediction of Standard Model (SM) processes can also lead a path to the discovery of new physics, which thus far has proven so elusive. Indeed, careful analyses of the QCD radiation pattern are crucial to distinguish Standard Model physics from possible new physics signals. In this context, studies of the internal structure of jets, i.e. jet substructure, have proved a valuable addition to LHC phenomenology. Furthermore, in order to obtain precise predictions, the jet substructure calculations usually involve resummation of the perturbative series, where large logarithms arise from the multi-scale hierarchy.
The aim of this thesis is to explore novel approaches to probe colour flow and soft substructure of jets, which is beyond the traditional boundaries of Perturbative Quantum Chromodynamics (pQCD), namely globalness and infrared & collinear (IRC) safety. In this thesis, the impact of non-global logarithms (NGLs) and IRC unsafe observables are studied in detail. In particular, for the non-global case, a novel approach to solving differential equations using artificial neural networks is presented, and we compare the results with the other methods in the literature. In the context of IRC unsafety, the first-principle calculation in resummed perturbation theory for the jet pull angle is performed, along with the resummation formalism is reviewed and improved. As phenomenological applications, each ingredient is studied independently. Moreover, because of the large theoretical uncertainty of IRC unsafe observable, the result is improved by introducing IRC safety projection for the jet pull vector. Additionally, with the purpose of assessing sub-leading colour correlations, the novel azimuthal asymmetry distribution is introduced and studied in some detail.
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Quintero, Masselski Christian Steven. "Conception des procédés par optimisation de superstructures pour l'usine du futur (PRO-FUTUR)." Electronic Thesis or Diss., Université de Lorraine, 2022. http://www.theses.fr/2022LORR0103.
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Selon les projections de l'Agence internationale pour les énergies renouvelables (IRENA), d'ici 2050, l'électricité sera le principal vecteur énergétique, avec une part de 50 % du marché de l'énergie. Le déploiement de la production d'énergie propre et son intégration au marché de l'énergie joueront un rôle clé dans la réalisation de cet objectif. De même, la recherche de procédés plus efficaces, durables et économiques est un défi important auquel les ingénieurs des procédés sont constamment confrontés dans la recherche et l'industrie, qui doivent généralement déterminer la meilleure configuration structurelle d'un procédé, conduisant à l'interconnexion optimale des unités opératoires, avec la mise en place respective des conditions d'exploitation. Cette tâche nécessite l'évaluation de plusieurs conceptions de processus pour trouver la meilleure configuration, ce qui est une approche épuisante et chronophage à exécuter manuellement. Par conséquent, ce travail est prévu pour permettre une méthodologie pratique pour les ingénieurs de processus d'évaluer de multiples alternatives de processus dans une superstructure unique, afin de déterminer la meilleure disposition structurelle, l'ensemble des conditions d'exploitation et/ou les paramètres de conception, menant à la configuration de processus optimale en ce qui concerne certains critères économiques, énergétiques et/ou environnementaux. La méthodologie est appliquée à un scénario de stockage d'énergie dans l'ammoniac, en utilisant comme référence le procédé conventionnel Haber-Bosch. Quatre superstructures de procédé ont été proposées et évaluées afin de déterminer la meilleure structure de procédé, qui inclut la sélection de : (i) le nombre de compresseurs dans l'étage de compression principal ; (ii) le nombre de réacteurs catalytiques ; (iii) le matériau catalytique, soit à base de Fe, soit à base de Ru ; (iv) la disposition des réacteurs, soit adiabatiques multi-lits, soit autothermiques multitubes ; (v) le système de refroidissement des réacteurs adiabatiques, soit indirect (AICR), soit direct (AQCR) ; (vi) l'utilisation d'une séparation intermédiaire ; (vii) la technologie de séparation, parmi le condenseur, les filtres à membrane et le PSA ; (viii) l'utilisation d'une égalisation de pression sur les flux de perméat des filtres à membrane ; (ix) l'utilisation d'un condenseur supplémentaire après la séparation par membranes ou par PSA. Les principaux résultats trouvés à travers l'optimisation de ces superstructures, ont permis de déterminer que le meilleur arrangement structurel consiste en deux réacteurs autothermiques en série, utilisant le catalyseur à base de Ru, avec deux étapes de compression, avec séparation intermédiaire et finale par condensation. Cette configuration permet de produire 3 994,8 tNH3/an, soit un LCOA de 790,3 €/t NH3, et une efficacité énergétique de 67,13 %. La consommation d'énergie spécifique du scénario complet est égale à 10,23 kWh/kgNH3, la meilleure technologie disponible pour la synthèse de l'ammoniac, basée sur l'hydrogène du gaz naturel, consommant 27,4 GJ/tNH3. Le principal moteur de la consommation d'énergie est l'électrolyseur, responsable de 9,09 kWh/kgNH3 (88,85 %), tandis que la production d'azote représente 0,68 kWh/kgNH3 (6,65 %), et la boucle de synthèse HB consomme 0,46 kWh/kgNH3 (4,50 %)Projections from the International Renewable Energy Agency (IRENA) support that by the year 2050, electricity will be the main energy carrier with 50 % of the share of the energy market. The deployment of clean energy production and its integration to the energy market will play a key role towards this objective. Also, the quest for more efficient, sustainable and economic processes is one important challenge that process engineers are constantly facing in research and industry, which commonly need to determine the best structural configuration of a process, leading to the optimal interconnection of the processing units, with the respective set up of the operating conditions. This task would require evaluating several process designs to find the best configuration, which is a tedious and time-consuming approach to execute manually. Therefore, this work is foreseen to enable a practical methodology for process engineers to evaluate multiple process alternatives within a unique superstructure, to determine the best structural arrangement, the set of operating conditions and/or design parameters, leading towards the optimal process configuration regarding some economic, energetic and/or environmental criteria. The methodology is applied to a scenario of energy storage in ammonia, using as reference the conventional Haber-Bosch process. Four process superstructures have been proposed and evaluated to determine the best process structure, which include the selection of: (i) the number of compressors in the main compression stage; (ii) the number of catalytic reactors; (iii) the catalytic material, either Fe-based or Ru-based; (iv) the reactor arrangement, either multibed adiabatic or multitube autothermal; (v) the cooling system for the adiabatic reactors, either indirect (AICR) or direct (AQCR); (vi) the use of intermediate separation; (vii) the separation technology, among the condenser, membrane filters, and PSA; (viii) the use of pressure equalization on the permeate streams of the membrane filters; (ix) the use of an additional condenser after the separation by membranes or by PSA. The main results found through the optimization of these superstructures, allowed to determine that the best structural arrangement consists of two autothermal reactors in series, using the Ru-based catalyst, with two stages of compression, with intermediate and final separation by condensation. This configuration allows to produce 3 994.8 tNH3/y, representing an LCOA of 790.3 €/tNH3, and an energy efficiency of 67.13 %. The specific power consumption of the complete scenario is equal to 10.23 kWh/kgNH3, with the best available technology for ammonia synthesis, based on hydrogen from natural gas, consuming 27.4 GJ/tNH3. The main driver of the energy consumption is the electrolyser, responsible for 9.09 kWh/kgNH3 (88.85 %), while the nitrogen production represents 0.68 kWh/kgNH3 (6.65 %), and the HB synthesis loop consumes 0.46 kWh/kgNH3 (4.50 %)
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Takase, Hiroshi. "Systematic Structure Synthesis of Distillation-Based Separation Processes." Kyoto University, 2018. http://hdl.handle.net/2433/232063.
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Zaika, S. A., A. G. Naumovets, A. T. Loburets, and D. V. Stryzheus. "Surface Diffusion and Phase Transitions in Ultrathin Films with Quasi-One-Dimensional Long-Period Structures." Thesis, Sumy State University, 2012. http://essuir.sumdu.edu.ua/handle/123456789/35015.
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The kinetics of surface diffusion in a submonolayer film with the structure p(1 × 4) on the (112) bcc
crystal surface in the region of a second order phase transition is investigated by molecular dynamics
method. It is shown that collective effects play an important role in the surface diffusion within films
where long-period chain structures are present. This is due to the strong anisotropy of the surface atomic
structure and lateral interaction of adatoms. Adatom chains which form a superstructure p(1 × N) block
the path of easy diffusion of individual atoms along the substrate grooves. With increasing temperature,
the diffusion coefficients increase rapidly because of the emergence of new vacancies in the chains. Domains
of a chain-like structure incommensurate with the substrate are formed in the adsorbed film when
passing through the critical temperature. The activation energy for diffusion decreases sharply at temperatures
above the critical one. The commensurate islands gradually disappear in the presence of the incommensurate
structure as the temperature increases. This increases the number of defects in the incommensurate
chain structure. Collective effects in the adsorbed film play an important role even at high
enough temperatures owing to fluctuations and destruction of interacting segments of the adatom chains.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/35015
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Zaika, S. A., and A. T. Loburets. "The Role of Submonolayer Film Structure in the Surface Diffusion on Atomic Anisotropic Crystal Face: a Computer Experiment." Thesis, Sumy State University, 2013. http://essuir.sumdu.edu.ua/handle/123456789/35175.
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We investigated the role of co-operative and structural effects in surface diffusion of adsorbed atoms with repulsive lateral interactions on the atomic anisotropic metal faces by computer simulation method. Such systems were been considered for which chain superstructures can be formed in submonolayer ad-sorbed films. It is shown that the diffusion coefficients D decrease rapidly with increasing coverage and is-land sizes in those concentration ranges where first order phase transitions take place. The dependence of D on concentration θ is pronounced very weakly in disordered films at temperatures above the critical one. Due to a crowdion mechanism, the diffusion coefficients are rising as the coverage increases in a homoge-neous film in the presence of chain superstructure. Chains commence to change often their positions in the range of critical temperatures. In such conditions, crowdion (quasi-point) configurations of adatoms can as-sociate into soliton-like (quasi-line) formations. The simulation results are compared with experimental data.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/35175
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Babii, Volodymyr. "Heterotopia: Loose Space For an Edge City." Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/74439.
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In the beginning of my research I focused on transformations of the urban leftover and void space found in between buildings, street networks, parks or other institutionalized public spaces into urban places of character.
By studying the spatial qualities of different places and their relation to human activities in those places I came up with the main question of my thesis: Can a space be designed loose and/or can it be loosened by design?
The concept of “heterotopia”, as described by Michel Foucault in his essay “Of Other Spaces: Utopias and Heterotopias”, is a place functioning in nonhegemonic conditions, the place of “otherness” that has more layers of meaning than meet the eye. That concept proved to be the best description and the bounding frame of the design part of my research.Master of Science
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祝新華 and Xinhua Zhu. "A study on the development of superstructure of narrativetext written by primary school pupils in Four Cities of China." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31242807.
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GONZALEZ, DE GALAVIS MARTHA ELENA. "Contribution au projet iron : calculs precis de donnees atomiques collisionnelles et radiatives a l'aide des codes rmatrx et superstructure." Paris 6, 1998. http://www.theses.fr/1998PA066503.
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Dans le cadre du projet international iron (ip), une serie de calculs precis de taux d'excitation par impact electronique et de taux de desexcitation radiative spontanee ont ete menes a l'aide des versions les plus recentes des programmes rmatrx et superstructure. Les ions choisis l'ont ete en raison de leur importance astrophysique. De nouvelles forces de collision effectives sont proposees pour deux ions du fer, fe xvi et fe xv, ainsi que pour plusieurs ions membres des sequences isoelectroniques du silicium et du soufre. Les modeles physiques retenus et les approximations choisies sont discutes en detail. L'importance d'une bonne representation de la structure des resonances dans les sections efficaces de collision, d'un traitement aussi rigoureux que possible des effets relativistes, ainsi que d'une bonne description quantique de l'ion-cible est demontree pour les cas etudies. L'efficacite de l'approximation du close-coupling (cc) est egalement confirmee. Le role crucial des ondes partielles de moment angulaire eleve est souligne. Apres analyse des resultats obtenus et comparaison avec les donnees disponibles precedemment, la precision des nouveaux taux de collision est estimee a 10-20% pour la grande majorite des transitions considerees. De nouvelles probabilites de transition radiative ont ete calculees pour les ions legers et moyennement lourds des sequences isoelectroniques du bore (complexe n = 2), du carbone et de l'oxygene (configuration fondamentale). Le formalisme de breit-pauli est mis en uvre pour traiter les effets relativistes. Les bases de configurations selectionnees l'ont ete apres une etude systematique des effets d'interaction de configurations. Apres construction ab initio d'une bonne representation des systemes electroniques etudies, une procedure semi-empirique de correction des energies des termes permet d'ameliorer encore la qualite des fonctions d'onde. Les probabilites resultantes sont analysees en detail et comparees aux meilleurs calculs publies. En conclusion, la precision des nouvelles donnees radiatives est estimee a 10 ou 20%, selon le type de transition, pour la plus grande part des raies etudiees. Les nouveaux resultats proposes ici seront bientot disponibles dans une nouvelle base de donnees, tiptopbase, installee au cds (observatoire de strasbourg).
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Grebík, Josef. "Cena bytu z pohledu investora." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2015. http://www.nusl.cz/ntk/nusl-227750.
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This master´s thesis deals with the issue of purchase of the apartment from the perspective of an investor. The aim of the thesis is to evaluate the possible variants of purchase of the apartment, while the main attention is focused on a comparison of the acquisition of an existing apartment, which requires reconstruction, and on the possibility of the construction of a new apartment in the form of loft conversion or superstructure. Possible variants of the solution are discussed in a broader context in order to determine the optimal variant for the investor.
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Pelissero, Marielle. "De l’underground à la superstructure : émergence de la notion de performance dans le discours critique des pratiques théâtrales expérimentales (1963-1973)." Thesis, Paris 10, 2016. http://www.theses.fr/2016PA100160.
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Au fil des trente dernières années, la notion de performance semble avoir acquis une place décisive dans le discours critique et esthétique du champ théâtral français. Cette étude vise à révéler les conditions dans lesquelles la notion de performance change de statut au sein du discours critique français, à travers une archéologie de la notion qui explore la décennie précédant son apparition dans le discours critique du théâtre en France. Il s’agit de rendre compte des débats et des frictions qui conduisent progressivement à cette émergence, à partir des discours des artistes, des organisateurs et des observateurs (spectateurs et critiques) des pratiques théâtrales dites expérimentales. La thèse étudie d’abord le discours de réseaux artistiques périphériques et parisiens de la période 1963-1968 : les premières éditions de la Semaine Sigma de Bordeaux, la branche Fluxus de l’École de Nice, ainsi que festival parisien de la Libre Expression qui présente le Théâtre Panique et organise des happenings. L’étude se concentre ensuite sur le discours relatif à la séquence 1969-1973 du Festival Mondial du Théâtre de Nancy. On y retrouve les mêmes concepts, exprimés cette fois au service d’un nouvel esprit du théâtre, dont l’enjeu consiste à établir un nouveau territoire critique et esthétique à même de garantir à la discipline théâtrale une place forte au sein de la société. De façon a priori paradoxale, les caractéristiques de la performance s’accordent à la fois aux pratiques théâtrales expérimentales et à une société marquée par l’économie capitaliste. De la contre-culture à la superstructure, cette historiographie tente de rassembler des éléments d’éclairage à cette problématiqueThroughout the past three decades, the notion of performance seems to have gained a crucial place in the French field of theatre’s critical and esthetical discourse. This dissertation intends to find out the conditions in which the notion of performance evolves inside the French critical discourse, exploring the decade preceding its advent in the critical discourse on theatre in France. The aim is to map an archaeology of the notion and to report the debates and frictions which progressively led to its emergence, out of the discourses of artists, curators and observers (spectators and critics) of the so-called experimental theatre practices. The study first analyses the discourse related to some artistic networks -peripheric and Parisian- during the 1963-1968 period, such as the first festivals Sigma in Bordeaux, the Fluxus branch of École de Nice, and the Parisian festival of Libre Expression, which presents the Panique Theatre and happenings. The dissertation then focuses on the discourse related to the 1969-1973 sequence of the International Theatre Festival of Nancy. One witnesses the same concepts, expressed this time in order to underwrite a new spirit of theatre, the stake of which is to set up a new critical and esthetical territory, able to ensure a stronghold position for the theatre field within the society. This historiography gathers elements to clarify how the features of performance can match both the experimental theatre practices and the society outlined by the capitalistic economy, from counter-culture to superstructure
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Matemu, Christian Hillary. "Development of a One-Way Coupled Diffraction/Trapped Air Model for Predicting Wave Loading on Bridge Superstructure Under Water Wave Attack." UNF Digital Commons, 2018. https://digitalcommons.unf.edu/etd/823.
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In recent years, a number of researchers have applied various computational methods to study wind wave and tsunami forcing on bridge superstructure problems. Usually, these computational analyses rely upon application of computational fluid dynamic (CFD) codes. While CFD models may provide reasonable results, their disadvantage is that they tend to be computationally expensive. During this study, an alternative computational method was explored in which a previously-developed diffraction model was combined with a previously-developed trapped air model under worst-case wave loading conditions (i.e. when the water surface was at the same elevation as the bottom bridge chord elevation). The governing equations were solved using a finite difference algorithm in MATLAB for the case where the bridge was impacted by a single wave in two dimensions. Resultant inertial and drag water forces were computed by integrating water pressure contacting the bridge superstructure in the horizontal and vertical directions, while resultant trapped air forces (high-frequency oscillatory forces or sometimes called “slamming forces” in the literature) were computed by integrating air pressure along the bottom of the bridge deck in the vertical direction. The trapped air model was also used to compute the buoyancy force on the bridge due to trapped air. Results were compared with data from experiments that were conducted at the University of Florida in 2009. Results were in good agreement when a length-scale coefficient associated with the trapped air model was properly calibrated. The computational time associated with the model was only approximately one hour per bridge configuration, which would appear to be a significant improvement when compared with other computational technique
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Sangirieva, Irina. "The design of an overpass crossing on railway in Mirny, Arkhangelska Oblast, Russia." Thesis, KTH, Bro- och stålbyggnad, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-90319.
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Bridge design and construction practice in former USSR, especially Russia, is not much known to the foreign engineers. Many advanced structural theories and construction practices have been established. In 1931, Franklin D. Roosevelt said, “There can be little doubt that in many ways the story of bridge building is the story of civilization. By it, we can readily measure a progress in each particular country.” The development of bridge engineering is based on previous experiences and historical aspects. Certainly, the Russian experience in bridge engineering has its own specifics. Bridge design proceeds in accordance with local standards and specifications. This study considers the basic rules and standards in bridge design in the North of Russia, the work includes the overview of Russian design concepts. The paper shows the design of typical concrete bridges including all calculations and analyses for future bridge stability and also drawings for visualisation. The results of the work are conclusions based on performing the required design calculations, drawings, preparing a final estimate and preparations for the construction. There are also some notes concerning the Russian design systems, computer programs for designing and computing and, finally, comparison of the Russians design standards and the Eurocode.
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McDonald, Christopher. "An experimental research investigation into disused flat rail wagons as bridges with applications for low volume rural roads in Australia." Thesis, Queensland University of Technology, 2011. https://eprints.qut.edu.au/45684/1/Christopher_McDonald_Thesis.pdf.
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An experimental laboratory investigation was carried out to assess the structural adequacy of a disused PHO Class Flat Bottom Rail Wagon (FRW) for a single lane low volume road bridge application as per the design provisions of the Australian Bridge Design Standard AS 5100(2004). The investigation also encompassed a review into the risk associated with the pre-existing damage in wagons incurred during their service life on rail.
The main objective of the laboratory testing of the FRW was to physically measure its performance under the same applied traffic loading it would be required to resist as a road bridge deck. In order to achieve this a full width (5.2m) single lane, single span (approximately 10m), simply supported bridge would be required to be constructed and tested in a structural laboratory. However, the available clear spacing between the columns of the loading portal frame encountered within the laboratory was insufficient to accommodate the 5.2m wide bridge deck excluding clearance normally considered necessary in structural testing. Therefore, only half of the full scale bridge deck (single FRW of width 2.6m) was able to be accommodated and tested; with the continuity of the bridge deck in the lateral direction applied as boundary constraints along the full length of the FRW at six selected locations. This represents a novel approach not yet reported in the literature for bridge deck testing to the best of the knowledge of the author.
The test was carried out under two loadings provided in AS 5100 (2004) – one stationary W80 wheel load and the second a moving axle load M1600. As the bridge investigated in the study is a single lane single span low volume road bridge, the risk of pre-existing damage and the expected high cycle fatigue failure potential was assessed as being minimal and hence the bridge deck was not tested structurally for fatigue/ fracture. The high axle load requirements have instead been focussed upon the investigation into the serviceability and ultimate limit state requirements. The testing regime adopted however involved extensive recording of strains and deflections at several critical locations of the FRW. Three locations of W80 point load and two locations of the M1600 Axle load were considered for the serviceability testing; the FRW was also tested under the ultimate load dictated by the M1600.
The outcomes of the experimental investigation have demonstrated that the FRW is structurally adequate to resist the prescribed traffic loadings outlaid in AS 5100 (2004). As the loading was directly applied on to the FRW, the laboratory testing is assessed as being significantly conservative. The FRW bridge deck in the field would only resist the load transferred by the running platform, where, depending on the design, composite action might exist – thereby the share of the loading which needs to be resisted by the FRW would be smaller than the system tested in the lab. On this basis, a demonstration bridge is under construction at the time of writing this thesis and future research will involve field testing in order to assess its performance.
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Koivisto, Markus, and Thomas Barthélemy. "Förstärkning av plattgrundläggning vid påbyggnad." Thesis, Malmö universitet, Malmö högskola, Institutionen för materialvetenskap och tillämpad matematik (MTM), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-43716.
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Befolkningsökningen och urbaniseringsprocessen gör att fler bostäder och andra byggnader måste uppföras i städerna. Stadsförtätning är en planeringsstrategi där påbyggnad av befintliga byggnader är en lösning. Vid påbyggnad måste nya laster bäras av en befintlig konstruktion och beroende på påbyggnadens omfattning och materialval används olika förstärkningsmetoder. Syftet med denna studie är att undersöka en förstärkningsmetod genom breddning av pelarfundament. Konsekvenserna inom två teknikområden: geoteknik och byggnads-konstruktion, har studerats. Frågeställningarna har varit likartade: vilka undersökningar måste göras och vilken bärförmåga har en konstruktion som pålastas före och efter förstärkning av pelarfundamentet? Parallellt med studier av litteratur har intervjuer med konstruktör och geotekniker utförts, för att skapa en tydlig inriktning på arbetet. Några metoder för förstärkning av pelarfundament presenteras. Förutom specialiserad litteratur, rapporter och uppsatser som utgör den största delen av teoriavsnittet i denna studie, har Eurokoderna utgjort referens, främst vid konstruktionsberäkningar men också för det avsnitt som berör geoteknik. För att kunna utföra relevanta beräkningar har ett fiktivt fall tagits fram. Utifrån bygghandlingar och uppmätningar i ett befintligt parkeringshus i Lund, har de vertikala lasterna före och efter påbyggnad beräknats. Den befintliga byggnaden var grundlagd på grov- och mellansand men placerades i det fiktiva fallet i Malmö och grundlades på lermorän. Utifrån de stipulerade förutsättningarna har en dimensionering vid förstärkning av det befintliga pelarfundamentet redovisats i form av beräkningskontroller samt ritningar. Vid dimensionering av pelarfundamentet har olika beräkningsmodeller använts. Flera avgränsningar har gjorts; exempelvis att horisontella laster inte beaktats och vertikala laster verkar centriskt, i syfte att ge en överskådlig bild av de vanligast förekommande beräkningarna och kontrollerna som måste göras vid fundamentförstärkning. I det aktuella fallet var sidan på det kvadratiska pelarfundamentet 2,8 m lång och dess tjocklek 0,6 m. De vertikala lasterna före påbyggnad uppskattades till 2242 kN och ökade till 3894 kN efter påbyggnad. Jorden blev då belastad nära maximal tillåten spänning och den befintliga betongkonstruktionen hade inte kapacitet för att bära de nya lasterna. En ökning av plattans breddmått med 0,45 m på samtliga sidor beräknades nödvändig för att behålla samma spänning i jorden. För att uppnå en godtagbar kapacitet antogs en pågjutning à 0,2 m också vara nödvändig. Även en breddning av den rektangulära pelaren antogs. Beräkningskontrollerna godkände de nya dimensionerna samt fastställde kvantiteten av nytt armeringsjärn som skulle användas, dels för att förlänga den befintliga armeringen, dels för att förbättra vidhäftningen mellan den gamla och den nya betongen. Val av förstärkningsmetod är förknippad med flera faktorer såsom läget inom byggnadskonstruktionen, geokonstruktionens skick, markförhållanden, mm. Därför är inte en metod bättre än en annan; lämplig metod måste bestämmas från fall till fall. Som studien visar skall en arbetsmetodik följas med undersökningar och relevanta beräkningar. Slutsatserna är att studiens resultat bedöms rimliga, men noggrannare dimensionering skulle kunna utföras med FEM-program.The increase in population and the urbanization process means that more buildings must be built in the cities. Extension of existing buildings is a solution to increase housing capacity, but the existing structure must be strengthened to be able to carry the new loads. The purpose of this study is to investigate a strengthening method of spread footing in two technical fields: geotechnics and building construction. The questions were: what investigations must be made and what load-bearing capacity has a structure that is loaded before and after enlargement of the spread footing? In addition to specialized literature, reports and essays, the Eurocodes have been a reference. Some methods for enlargement of spread footing are presented. A fictitious case has been developed based on construction documents and measurements in an existing parking garage that was placed in Malmö and founded on clay till. A dimensioning for enlargement of the existing spread footing has been reported in the form of calculation checks and drawings. The vertical loads before the extension were estimated at 2242 kN and increased to 3894 kN after the extension. An increase in the width of the footing by 0.45 m on all sides was calculated necessary to maintain the same tension in the ground. In order to achieve an acceptable capacity, an overlay of 0.2 m was also assumed to be necessary. The calculation controls approved the new dimensions and determined the quantity of new dowels to be used, partly to extend the existing reinforcement, partly to improve the adhesion between the old and the new concrete. The choice of enlargement method is associated with several factors therefore, one method is not better than another. The appropriate method must be determined on a case-by-case basis with a working methodology with surveys and relevant calculations. The conclusions are that the results of the study are considered reasonable, but more accurate dimensioning could be performed with FEM-programs.
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Bauer, Karel. "PROMĚNA AREÁLU BRNĚNSKÝCH VELETRHŮ /Transformace západní části areálu BVV/." Master's thesis, Vysoké učení technické v Brně. Fakulta architektury, 2018. http://www.nusl.cz/ntk/nusl-377211.
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Brno trade fairs are the heart of Central Europe for exhibitions of everything interesting for already more than 90 years. Nevertheless, the most valuable exhibits are the urban and architectural values of the complex, which are reflecting the development of modern Czech architecture. Even after years of development, it is still necessary to look to the future, to solve the coming problems of generosity, to keep the high level of the area, to support its function and to keep legacy of the fairs for the next generation. As the main happenings moves further from the city centre, the issue is still more up to date on how to handle the west side of this area. In my work, I set out clearly the future urban planning of the trade fairs and divide the various functions into logically integrated areas. In the west part, I am creating a new administrative centre with a lot of other associated services. The basic idea is to create a permanent supporting superstructure, into which the variable function is inserted. I take advantage of the basic principles of smart city, flexibility and the versatility of buildings. To achieve a good connection of the complex with the surrounding area, I maintain the existing transport connections and make new possibilities of movement through the complex and the surrounding areas. This creates a new modern part of the complex, which could evolve over time based on the needs and requirements of its users.
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Samaké, Oumar. "Analyse thermo-économique d'un système de dessalement par thermocompression de vapeur et conception de l'éjecteur." Thèse, Université de Sherbrooke, 2016. http://hdl.handle.net/11143/8782.
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L’objectif de cette thèse est de présenter les travaux d’une analyse thermo-économique d’un système de dessalement par distillation dans l’optique de revaloriser les pertes thermiques industrielles. Les rejets en question sont ceux d’un moteur Diesel utilisé dans une centrale de production d’électricité.
Premièrement, une étude préliminaire est faite en utilisant un modèle boite noire. L’optimisation des fonctions objectives de ce modèle a permis de déterminer les paramètres de conception.
Ensuite un nouveau modèle d’éjecteur distinct des deux modèles classiques utilisés en thermodynamique (à pression et à section constante) est développé. Les performances des procédés de détente et de compression dans cet éjecteur sont calculées en appliquant un rendement polytropique comme dans les turbomachines. La méthode développée a permis de déterminer toutes les dimensions de l’éjecteur ainsi que la position de l’onde de choc.
Enfin une analyse détaillée du système de dessalement est faite pour déterminer le nombre d’effets ou cellules et les conditions qui permettent de satisfaire les conditions optimales obtenues lors de l’analyse préliminaire. L’analyse thermodynamique se base sur un tout nouveau modèle mathématique qui permet de simuler à la fois les deux configurations les plus utilisées en dessalement. De plus, une analyse thermo-économique basée sur l’exergo-économie a permis de calculer le coût de production et les investissements nécessaires.
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Graciano, José Eduardo Alves. "Síntese ótima de processos não isotérmicos de tratamento de efluentes." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/3/3137/tde-27092012-103217/.
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As metodologias para a síntese de processos, baseadas em otimização de superestruturas, mostram-se mais poderosas do que as baseadas no projeto em heuríticas, já que levam em consideração as inúmeras possibilidades de construção do processo. É pratica comum a utilização de modelos simplificados (como modelos de rendimento), na representação dos equipamentos dentro destas superestruturas, uma vez que a utilização de modelos fenomenológicos tornar-se-ia inviável, devido aos tempos computacionais e à dificuldade técnica de se programar os módulos e propriedades termodinâmicas de um simulador comercial, dentro de uma plataforma de otimização como o GAMS. Modelos com alta precisão, que não requerem grandes tempos computacionais, reduzidos ou de superfície de resposta, aproximam modelos fenomenológicos e podem ser introduzidos em problemas de síntese, obtendo soluções mais precisas. Neste trabalho, foram construídos modelos reduzidos para dois processos comumente encontrados em sistemas de tratamento de efluentes de refinarias de petróleo: uma torre de resfriamento e um stripper de vapor. Os dados utilizados para a correlação dos modelos reduzidos foram gerados, através da simulação de modelos semi-fenomenológicos ou fenomenológicos destes equipamentos. É proposta uma metodologia original para gerar modelos reduzidos, que diferentemente dos trabalhos anteriores em que se utilizam modelos reduzidos tipo caixa preta, emprega-se um modelo reduzido tipo caixa cinza para a representação da coluna de stripper, o que aumenta a capacidade de correlação do modelo ao conjunto de dados, resultando em menores erros de predição. Dois tipos clássicos de modelos reduzidos foram utilizados dentro dos modelos caixa-cinza: um modelo baseado em redes neurais e um modelo polinomial. Ambos mostraram-se capazes de representar o modelo fenomenológico com pequenos erros e permitindo resolver o problema de síntese em um tempo computacional razoável (da ordem de 10 segundos). Nota-se também que são obtidas várias soluções ótimas locais que diferem ligeiramente de acordo com a abordagem utilizada, mas que qualitativamente correspondem a um mesmo conjunto de soluções.The superstructure optimization-based methodologies for process synthesis can be more powerful than the heuristic based methodologies, because they cope the many possibilities in order to design the process. It is common practice to use simplified models (efficiency-based models), in the representation of equipment in the superstructures, because the use of phenomenological models would be unfeasible due the high computational time and the technical difficulties in order to program module and thermodynamics properties packages of commercial simulators, into an optimization platform as GAMS. High accuracy models, which do not require large computational time, can be obtained using different types of surrogate or response surface, approximate phenomenological models of the system and can be introduced into the synthesis problems, leading to more precise solutions. In this work, surrogate models were built for two processes usually found in water treatment networks in petroleum refineries: a cooling tower and a steam stripper. The data sets used for fitting the surrogate model were generated by the semi-phenomenological or the first principles model of those equipment. An original methodology for generating surrogate model is proposed that differently of previous works (which make use of black box surrogate models) uses gray box models to represents de stripper column. This approach improves the correlation capacity of the surrogate model to the set data and reduces the prediction errors. Finally, two classic surrogate models were used inside the gray-box models: a neural network based model and a polynomial model. The results showed that both are able to represent the phenomenological model with small errors to solve the synthesis problem in a short computational time (which not exceed in a magnitude of 10 seconds). It is noticed also that many local solutions are obtained, these differ slightly depending on the approach used, but qualitatively represent the same set of solutions.
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Zhao, Qiao. "Conception and optimization of supercritical CO2 Brayton cycles for coal-fired power plant application." Thesis, Université de Lorraine, 2018. http://www.theses.fr/2018LORR0080/document.
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L'amélioration des systèmes énergétiques est considérée comme un levier technologique pour répondre aux défis liés à la croissance de la demande d’électricité et des émissions des gaz à effet de serre. Les futures centrales devraient présenter une intégration thermique plus flexible et des sources de chaleur mixtes possibles. Une des solutions fiables consiste à utiliser un cycle de Brayton au CO2 supercritique (CO2-SC), un tel cycle à haut rendement est théoriquement prometteur pour les applications nucléaires, fossiles et solaires thermiques. Un des principaux obstacles au déploiement du cycle de Brayton au CO2-SC est de justifier sa faisabilité, sa viabilité et son potentiel à l’échelle industrielle. Dans ce contexte deux axes de recherche ont été identifiées : • Une sélection rigoureuse de l’équation d’état qui permet de représenter les propriétés d’intérêt du CO2-SC. • Une nouvelle méthodologie pour l’optimisation des centrales électriques, permettant de sélectionner automatiquement le procédé optimal parmi une grande quantité de configurations possibles (dénomme superstructure). Les résultats de la première partie de cette thèse mettent en lumière que l’équation de SW est pertinente pour limiter l’impact de l’imprécision de l’équation d’état sur le dimensionnement du procédé. Dans cette thèse, un simulateur de procédé commercial, ProSimPlus a été combiné avec un solveur type évolutionnaire (MIDACO) afin d’effectuer des optimisations superstructure. Premièrement, le critère d’optimisation est de maximiser le rendement énergétique du procédé. Dans un deuxième temps, on cherche simultanément à minimiser les coûts du procédé. Pour ce faire, des fonctions de coût internes à EDF ont été utilisées afin de permettre l’estimation des coûts d'investissement (CAPEX), des dépenses opérationnelles (OPEX) et du coût actualisé de l'électricité (LCOE)Efficiency enhancement in power plant can be seen as a key lever in front of increasing energy demand. Nowadays, both the attention and the emphasis are directed to reliable alternatives, i.e., enhancing the energy conversion systems. The supercritical CO2 (SC-CO2) Brayton cycle has recently emerged as a promising solution for high efficiency power production in nuclear, fossil-thermal and solar-thermal applications. Currently, studies on such a thermodynamic power cycle are directed towards the demonstration of its reliability and viability before the possible building of an industrial-scale unit. The objectives of this PhD can be divided in two main parts: • A rigorous selection procedure of an equation of state (EoS) for SC-CO2 which permits to assess influences of thermodynamic model on the performance and design of a SC-CO2 Brayton cycle. • A framework of optimization-based synthesis of energy systems which enables optimizing both system structure and the process parameters. The performed investigations demonstrate that the Span-Wagner EoS is recommended for evaluating the performances of a SC-CO2 Brayton cycle in order to avoid inaccurate predictions in terms of equipment sizing and optimization. By combining a commercial process simulator and an evolutionary algorithm (MIDACO), this dissertation has identified a global feasible optimum design –or at least competitive solutions– for a given process superstructure under different industrial constraints. The carried out optimization firstly base on cycle energy aspects, but the decision making for practical systems necessitates techno-economic optimizations. The establishment of associated techno-economic cost functions in the last part of this dissertation enables to assess the levelized cost of electricity (LCOE). The carried out multi-objective optimization reflects the trade-off between economic and energy criteria, but also reveal the potential of this technology in economic performance
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Valero, Carlos Alberto Mojica. "Efeito da superestrutura sobre a resistência longitudinal de embarcações de pequeno porte: aplicação e análise estrutural para um navio militar da Marinha Colombiana." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/3/3135/tde-13082008-151753/.
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O propósito do presente trabalho é desenvolver a avaliação estrutural de um navio \"Nodriza\" de pequeno porte de aplicação militar e cujo projeto inicial foi orientado à navegação em águas abrigadas com restrições de calado. Porém, requisitos e necessidades afetando a concepção inicial do projeto obrigam este a efetuar percursos em águas profundas com possibilidade de experimentar ciclos de onda. A avaliação estrutural pretende determinar o nível de influência da superestrutura sobre a resistência longitudinal do navio considerando-o submetido a esforços solicitantes próprios de águas não abrigadas. As limitações geradas pelas formas e proporções do navio Nodriza, que não permitem implementar de forma direta as regras de Sociedades Classificadoras para a avaliação estrutural em águas profundas, obriga ao uso de cálculos diretos para sua aprovação. Uma análise mediante o uso de elementos finitos, modelando o navio com e sem participação da superestrutura, permite determinar como esta representa uma significativa influência sobre a resistência longitudinal e tensões finais dos membros principais e membros de suporte, quando é considerada dentro da análise estrutural. Igualmente, implementam-se procedimentos determinísticos propostos pelas regras de sociedades classificadoras para navios convencionais, na procura de estabelecer a conveniência ou não da sua aplicação como método de aproximação para uma avaliação estrutural desta classe de navio militar, cujas características tornam dele um caso particular de análise.The objective of the present work is to conduct a structural evaluation of the small size, military vessel Nodriza which has been designed for navigation in sheltered waters with draft restrictions. However, new requirements and changes in the operation of this vessel forced deep water navigation with the possible action of wave loading. The structural evaluation seeks to determine the effects of the superstructure on the longitudinal structural resistance for the vessel. Since the geometry and overall dimensions of the ship are not covered by the structural rules of the Classification Societies, a numerical analyses based on the finite element method is conducted for a full model of the vessel. The numerical analyses demonstrate the strong effect of the superstructure on the longitudinal resistance which yields reduced stress levels in primary structural members. The work provides a compelling support to use more refined procedures in the structural design of non-conventional small-sized vessels.
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Lucian, Charles. "Geotechnical Aspects of Buildings on Expansive Soils in Kibaha, Tanzania : Preliminary Study." Licentiate thesis, Stockholm : Division of soil and rock mechanics, Royal Institute of Technology, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4056.
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Siveris, Daiane. "Política de constituição do dicionário Caldas Aulete Digital." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2018. http://hdl.handle.net/10183/179407.
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Nesta pesquisa tivemos como objetivo explicitar a política de constituição do Dicionário Caldas Aulete Digital a partir da compreensão do funcionamento da concepção de língua veiculada nesse dicionário, uma vez que esta se constitui na tensão entre infraestrutura e superestrutura. Analisamos o funcionamento do conceito de língua na relação entre infraestrutura e superestrutura; compreendemos o conceito de política e suas relações com o sentido; apresentamos as especificidades e as condições de produção do Dicionário Caldas Aulete Digital, pensando a reformulação, do Dicionário Houaiss e do Dicionário Aurélio para entender que relações se estabelecem entre esses diferentes dicionários e buscamos apresentar o espaço de reformulação na articulação com as práticas sociais. O percurso teórico desenvolvido teve por base o materialismo histórico e dialético, perpassando também pelos estudos filológicos, estudos linguísticos estruturalistas e culminando nos estudos discursivos. Com os estudos filológicos de Michel Bréal, entendemos que a linguagem reflete o homem, suas vontades e seus desejos, remontando à condição humana de sujeito histórico e responsável pelas mudanças em uma língua. Os estudos linguísticos estruturalistas de Ferdinand de Saussure apontam a língua como objeto abstrato, cujas alterações ocorrem no deslocamento da relação entre o significante e o significado, sem qualquer interferência externa à língua, limitando-se o objeto língua, portanto, a um sistema estável. Os estudos materialistas de Mikhail Bakhtin/Valentin Volochínov abordam a linguagem enquanto materialidade, cujas condições de uso remetem aos sentidos, logo em funcionamento na realidade concreta de uso. Nos estudos discursivos de Michel Pêcheux, o conceito de língua está articulado ao de discurso, para o qual a língua serve de suporte para a realização dos efeitos de sentido. O conceito de política abordado a partir de Hannah Arendt está articulado ao de liberdade e é a criação do novo, do inesperado, é ação plural, sendo inerente à condição humana. Para Jacques Rancière, a política se instaura com o dano e este desfaz a ordem policial instituída, rompendo com a configuração da sociedade em que se definem as parcelas. Na teoria de Michel Pêcheux, observamos que a política se relaciona com o conceito de formação discursiva, pois é nesta que as palavras adquirem seus sentidos a partir da inscrição dos sujeitos em determinada formação ideológica. Para as análises, selecionamos verbetes que contribuíssem para ilustrar as relações infraestruturais e superestruturais que se estabelecem na produção do dicionário, bem como que possibilitassem a articulação com os conceitos estudados. As análises centraram-se, ainda, nos projetos da editora Lexikon e permitiram apresentar que no projeto inicial de produção dicionarística visava-se a uma obra aberta, de dicionarização da língua viva, isto é, a língua em funcionamento na sociedade, reflexo das práticas dos sujeitos na infraestrutura e na superestrutura, cuja contribuição era estendida aos sujeitos falantes da língua, leigos quanto aos critérios lexicográficos de constituição de um dicionário. No projeto seguinte, reformulado, há um retorno aos dicionários clássicos e tradicionais, pois há um controle sobre a dicionarização na medida em que o sujeito das forças orgânicas não pode mais contribuir com a produção desse dicionário, e a tarefa da lexicalização da língua retorna aos lexicógrafos, sujeitos academicamente instruídos para tal.In this research we have aimed to explicit the politics of constitution of Caldas Aulete Digital Dictionary, starting from the comprehension of the functioning of the concept of language assumed in this dictionary, since this language is constituted by the tension between infrastructure and superstructure. We analyzed the functioning of the concept of language in the relationship between infrastructure and superstructure; we comprehended the concept of politics and its relations with meaning; we pointed the specificities and the conditions of production of Caldas Aulete Digital Dictionary, considering the reformulation of Houaiss Dictionary and Aurélio Dictionary in order to understand what relations are established between these different dictionaries, and we sought to present this space of reformulation in the articulation with social practices. The theoretical course developed was based on historical and dialectical materialism, also going through philological studies, structuralist linguistic studies, culminating in discursive studies. With Michel Bréal’s philological studies, we understand that language reflects the human being, its wills and desires, reinforcing the human condition of historical subject, responsible for changes in a language. The structuralist linguistic studies of Ferdinand de Saussure point to language as an abstract object, whose alterations occur in the displacement of the relation between the signifier and the signified, without any language external interference, thus limiting the language object to a stable system. Materialistic studies of Mikhail Bakhtin / Valentin Volochínov approach language as materiality, whose conditions of use refer to meaning, therefore, in functioning in the concrete reality of use. In discursive studies of Michel Pêcheux, the concept of language is articulated to the concept of discourse, to which the language serves as support for the accomplishment of the effects of meaning. The concept of politics taken from Hannah Arendt is articulated to the notion of freedom and it is the creation of the new, the unexpected, it is plural action and inherent to the human condition. To Jacques Rancière, politics is established with the damage and this damage undoes the police order instituted, breaking with the configuration of the society in which social classes are defined. In Michel Pêcheux’s theory, we observe that politics is related to the concept of discursive formation, as the words acquire their meaning inserted in such discursive formation, from the inscription of the subjects in a certain ideological formation. For the analysis, we selected entries which could contribute to illustrate the infrastructural and superstructural relations that are established in the production of the dictionary, as well as entries that could enable the relation with the concepts addressed. Such analysis also focused in the projects of Lexikon editor and allowed to present that in the initial project of the dictionary production an open work was aimed; a work of living language in the dictionary, that is, the functioning language in society, as a reflection of the practice of the subjects in infrastructure and superstructure, whose contribution was extended to the language speaking subjects, lay people when it comes to lexicographic criteria of the constitution of a dictionary. In the following project, redesigned, there is a return to classical and traditional dictionaries, as there is a control on the entries inclusion in the extent that the subject of organic forces can no longer contribute to the production of such dictionary, and the task of lexical establishment returns to lexicographers, subjects who are academically instructed to do so.